This invention pertains to a retractable, self-ventilating, self-stopping pouring spout assembly for use when pouring liquid from a supply container to a target container. The spout assembly is of the type where liquid flow is automatically stopped when the fluid level in the target container reaches a desired level.
With pouring spouts, several problems can occur when transferring liquid from a supply container to a target container. Once the supply container is tipped to begin the transfer, liquid tends to surge down the spout, often reaching the spout exit opening before the spout tip is safely inside the target container. If the liquid is flammable or toxic, a dangerous spill can occur at the time liquid is just starting to be transferee. If high temperature sources are nearby, such as a chain saw or a lawn mower, the spill can become a significant safety hazard at the time the liquid is being transferee.
Furthermore, as the target container becomes full, conventional spout must be tilted rapidly upright to raise the exit opening of the spout above the liquid level in the supply container, for otherwise, an additional spill would occur through the pouring spout.
Spout assemblies are known which stop the liquid flow once the surface of the liquid in the target container rises above a predetermined level. These spout assemblies typically have a elongate vent that extends from the supply container into a target container. When the fluid level in the target container reaches an air intake opening in the vent, flow is stopped. For example see U.S. Pat. No. 4,588,111 to Hestehave. As the liquid rises above the air intake opening in the vent, suction is created in the supply container which stops the flow of additional liquid.
Spout assemblies typified by the Hestehave spout do not solve the problem of preventing spillage when the spout connected to the supply container is initially tilted into the target container, nor do these assemblies solve the problem of preventing spillage when the vented spout is removed from the target container. When conventional spouts are lifted above the surface of the liquid in the target container, the suction in the supply container is broken and the liquid will resume flowing in the spout until the spout exit opening is raised above the surface level of the liquid in the supply container.
From the above it can be seen that a need exits for a spout assembly which can be placed in a target container with the flow of liquid through the spout initially stopped when the spout is inserted into the target container. Further a need exits for a spout assembly that prevents spillage when the spout assembly is lifted from the target container and tilted to an upright resting position.